In traditional trigate liquid crystal display panel, the high pin count is provided for the IC of the source of the transistor for reducing the cost. However, only one IC and one group of fanout provided in the source would cause a great difference in the resistances of the fanouts. In practice, if the difference of the resistances is too large, a phenomenon of color cast would occur on the periphery area of the display panel while the image with mixing colors is displayed. For example, when the display panel displays the image with mixing colors, the data line charges two sub-pixels, and then charges the next two sub-pixels. If the resistance of fanout is too large, RC delay would be serious. Thus, the second sub-pixel can be charged well than the first sub-pixel while charging. Especially in the periphery area of the display panel, the resistance of the fanout reaches its maximum point; and the RC delay is relatively serious, which cause a phenomenon of colorcast.
FIG. 1A shows a conventional layout of the traditional trigate liquid crystal display panel with a source provided with high pin count, while the display panel displays the image with blue and redmixing colors (at the time, the green sub-pixel have not been charged). The scanning lines scan from top to bottom. The difference between the resistances of the fanouts in the central area and in the periphery area of the display panel is large, the extents of RC delay in the data line are different from each other, and the RC delay would be more serious in the periphery area of the display panel. When the red sub-pixel and blue sub-pixel work, the blue sub-pixel can be charged firstly, and then the red sub-pixel is charged. Referring to FIG. 1B through FIG. 1D, since the RC delay in the periphery area of the display panel is serious, the blue sub-pixels in the periphery area of the display panel may be charged lower than the red sub-pixels. Thus, when a purple image is displayed on the periphery area of the display panel, the purple image may present red color cast. If the scanning lines scan in an opposite direction, the purple image may present blue color. Such phenomenon of color cast also occurs on the display panel while displaying yellow image, blue image and so on.
FIG. 2 shows a layout of the conventional trigate liquid crystal display panel. The reference number D1 to D5 denote data lines. The reference number G1 to G10 denote scanning lines. The numbers in circle denote the serial numbers of fanout circuits. In the traditional layout, the data line can charge the sub-pixels in an order as follows: R→G→B→R→G→B.
FIG. 3 is a schematic view illustrating waveforms for driving some of scanning lines of the conventional trigate liquid crystal display panel. Vgh denotes high level. When the scanning line is fed the high level Vgh, the transistor connected with the scanning line turns on, and corresponding pixels can be charged. Vgl denotes low level. When the scanning line is fed the low level, such transistor turns off. The signal from fanout circuit drives the scanning lines to work in an order: 1, 2, 3, . . . , 2n−1, 2n, thus can cause a color castoccurredon the periphery area of the display panel.